Spring Flight Research Articles

Seasonal and Spatial Dispersal Patterns of Select Ambrosia Beetles (Coleoptera: Curculionidae) from Forest Habitats into Production Nurseries

Abstract Exotic ambrosia beetles (Coleoptera: Curculionidae) are important pests of ornamental tree nurseries. Although these beetles reportedly disperse in early spring from peripheral forested areas into nurseries, few studies have determined how far they fly to infest new host trees, or whether a masstrapping strategy can adequately protect a nursery crop. Field monitoring with ethanol baits in South Carolina (2011–2012), Mississippi (2013–2014), and Louisiana (2013–2014), USA, determined the timing of peak ambrosia beetle flights, dispersal distance, and optimal trap location. In addition to the well-documented spring flight peak, southeastern nursery managers may need to be aware of a second, late-summer flight. Captures from traps placed in a nursery at various distances (−25 to 200 m) from the forest—nursery interface showed a significant linear and quadratic trend in decreasing numbers of beetles captured with increasing distance from the forest in South Carolina, whereas significant linear, quadr...

Seasonal response ofNoctua pronubaLinnaeus, 1758 (Lepidoptera: Noctuidae) to traps in Washington State

Noctua pronuba Linnaeus, 1758 (Lepidoptera: Noctuidae), the yellow underwing moth, was recently introduced into western North America. Blacklight traps at multiple sites in eastern Washington State indicate two broad periods of moth flight. A spring flight was evident in May and June, and a late season flight was evident from late August into October. Noctua pronuba moths were captured also in traps baited with acetic acid plus 3-methyl-1-butanol, but not in traps baited with acetic acid or 3-methyl-1-butanol alone. This chemical combination is thought to be a feeding attractant for many noctuid moths and may be useful for monitoring N. pronuba. The seasonal pattern of moths captured in traps baited with this chemical lure was similar to the pattern seen with blacklight traps.

Onion thrips, Thrips tabaci (Thysanoptera: Thripidae), overwintering in South Auckland, New Zealand: the importance of the local bionomic data/temperature model and biosecurity implications

Onion thrips flights in winter and early spring 1999 were monitored in South Auckland using sticky traps and trap plants. A pair of yellow sticky traps and 10 ‘thrips-free’ onion pot plants per site were changed every 2 weeks. Thrips were detected on traps and plants in June, September and October. Sticky traps were the most reliable method for detecting thrips flights. Wild plants were inspected four times and revealed that thrips bred all winter. There was no diapause. Seedlings that had sprouted in mid July had second instar larvae by 4 October 1999. The nearest source was self-set plants in an adjacent field. Three published temperature models for onion thrips development were compared. Generation times were similar in summer, but very different in winter. The Texas model with minimum developmental threshold of 11.5 °C had the longest winter generation time and required a thrips flight by early August for second instar larvae to develop in the crop by 4 October, whereas the South Auckland model (threshold 8.7 °C) required flights by early September. Thrips flights were detected by traps in September but not August 1999. For cosmopolitan pests that are very variable genetically, it is important to generate local biological data. The biosecurity implications of this variability are discussed.

Choice or constraint: Plasticity in overwintering sites of the European spruce bark beetle

Winter mortality is an important driver in bark beetle population dynamics. Overwintering site – be it in the soil or within the tree – can influence mortality, because temperature dynamics can differ between soil and tree at the same site. For Ips typographus L. (Coleoptera, Curculionidae, Scolytinae), it is not yet definitely resolved which of the two aforementioned is its overwintering site. Both sites, sometimes even mixed within the same population, have been reported in earlier studies. Here we studied the underlying mechanism of soil overwintering in I. typographus. We used soil emergence traps at the base of infested trees with variable amounts of fallen bark during winter. The number of soil overwintering beetles increased with increasing amount of fallen bark and decreased with increasing distance from the stem base of infested trees. Removing the bark beneath soil emergence traps resulted in a smaller number of emerged beetles, indicating that a majority of beetles was located in the fallen bark and not in the litter. Thus, soil hibernation in our study area in Central Europe occurred passively, mediated through falling bark.Furthermore, we studied post-diapause fitness in terms of body weight and lipid reserves in dependence of overwintering site (tree vs. soil). Fresh and dry masses of beetles were higher before than after winter, but not different after winter between overwintering sites. Lipid reserves were more depleted in tree overwintering beetles. Thus, the soil seems to be more advantageous as overwintering site from an energetic point of view. However, both possible overwintering sites have different other advantages and mortality risks regarding onset of flight in spring, inoculative freezing, fungal infection or predation risk.The mixed overwintering sites, caused by individuals’ active movement to the drier part of the bark and remaining in the stem or a passive dropping to the soil via fallen bark, spread winter mortality risks within populations and thus may contribute to local population stability. This phenomenon complicates forest management measures because a considerable number of beetles may be hibernating within fallen bark on the ground. Thus, when trees infested during the summer swarming period are not removed as long as bark is still in close contact with the stem, a great number of beetles can remain in the forest within fallen bark, even when trees are removed at a later point.

Seasonal flight activity, phenology and physiological status of the major establishment pests ofEucalyptus nitensplantations,Heteronyx dimidiataandH. crinitus(Coleoptera: Scarabaeidae: Melolonthinae)

Heteronyx dimidiata and H. crinitus are significant pests of young Eucalyptus spp. plantations in Tasmania, but little is known about their biology. Adult beetles feeding on the leaves and developing leaf buds of young seedlings can severely affect their growth and form or even kill them. Yellow-vaned funnel traps were used to monitor the flight activity of Heteronyx in a commercial plantation over 3 years. Visual searches were also conducted to determine the incidence of inactive beetles in the soil underneath trees and the presence of active beetles on leaves. Over 12 000 H. dimidiata and 1300 H. crinitus were collected during the study. The pattern of trap captures was similar in both species with over 90% of beetles being caught in spring and low numbers being caught throughout summer and autumn. High numbers of H. dimidiata were found in the soil surrounding the roots of Eucalyptus nitens seedlings, but very few larvae were present, indicating that oviposition occurs outside these plantations. Trap data suggest that spring flight activity is principally due to the emergence of overwintering adult beetles and that newly eclosed beetles typically invade plantations during late summer/autumn. Spring trap captures were strongly male biased, suggesting a scramble mating system where males were more active as they competitively searched for females. Over 65% of the variation in H. dimidiata activity in spring was accounted for by levels of solar radiation and wind. Females mated up to three times and ovarian development usually commenced in spring. The incidence of food in the crop was highest during autumn/winter, but the presence of fat in the abdomen was similar throughout the year. The use of yellow-vaned funnel traps to monitor the flight activity of diurnally active Heteronyx species in commercial Eucalyptus spp. plantations is recommended.

Nocturnal passerine migrants fly faster in spring than in autumn: a test of the time minimization hypothesis

It has been suggested that time selection and precedence in arrival order are more important during spring than autumn migration. Migrating birds are expected to fly at faster airspeeds if they minimize duration rather than energy costs of migration, and they are furthermore expected to complete their journeys by final sprint flights if it is particularly important to arrive at the destination before competitors. We tested these hypotheses by tracking-radar studies of nocturnal passerine migrants during several spring and autumn seasons at Lund (56°N) and Abisko (68°N) at the southern and northern ends of the Scandinavian Peninsula, respectively. The samples from these two sites represent migrants that are mostly rather far from (Lund) or close to (Abisko) their breeding destinations. We found that the birds were flying at clearly faster airspeeds in spring than in autumn at both study sites, with spring speeds exceeding autumn speeds by, on average, 16%, after taking effects of wind conditions and vertical flight speeds into account. This difference in speeds could not be explained by seasonal differences in body mass or wing morphology and thus supports the hypothesis of time-selected spring migration. There was also a significantly larger seasonal difference in airspeed at Abisko than at Lund, suggesting that the birds may have shown an inclination to sprint on their final spring flights to the breeding destinations, although this possible extra sprint effort was modest.

Monitoring Flight Activity of Ambrosia Beetles in Ornamental Nurseries with Ethanol-Baited Traps: Influence of Trap Height on Captures

Abstract Ethanol-baited bottle traps were used to monitor spring flight activity of the ambrosia beetles Xylosandrus crassiusculus and Xylosandrus germanus in Ohio, Tennessee, and Virginia. The traps were deployed at three different heights to determine if height influenced captures. X. germanus was captured in all three states, while X. crassiusculus was captured in TN and VA only. Traps 0.5 m above the ground captured more X. germanus than traps at 1.7 or 3.0 m. Traps 0.5 or 1.7 m above the ground captured more X. crassiusculus than traps at 3.0 m. In TN and VA, first activity of X. crassiusculus and X. germanus occurred from mid-March to early April. In OH, first activity of X. germanus occurred early to mid-April. Analysis of attacks by X. germanus on Cornus florida revealed that more than 90% of the attacks occurred on the main trunk within 1 m (3 ft) of the ground. Monitoring will be most effective when traps are suspended 0.5 or < 1.7 m above the ground for X. germanus or X. crassiusculus, respectively. To detect first flight of X. crassiusculus or X. germanus, traps should be deployed by early to mid-March in TN and VA and late March in OH.

Aphids in the face of global changes

Global warming is one of the principal challenges facing insects worldwide. It affects individual species and interactions between species directly through effects on their physiology and indirectly through effects on their habitat. Aphids are particularly sensitive to temperature changes due to certain specific biological features of this group. Effects on individuals have repercussions for aphid diversity and population dynamics. At a pan-European scale, the EXAMINE observation network has provided evidence for an increase in the number of aphid species present over the last 30 years and for earlier spring flights. We review these results and provide a review of the principal effects of global warming on aphid communities.

Predicting the vulnerability of New Zealand radiata pine plantations to the European pine weevil

Summary The European pine weevil, Hylobius abietis, is an important pest of temperate conifers and a significant biosecurity threat to countries such as New Zealand (NZ) where commercial forestry is largely dependent on pine monoculture. The economic impact of this insect is determined by its abundance and the degree of resistance of young pines to adult feeding. Assessing the likely impact of pine weevil in the event of accidental introduction is an important part of contingency planning. Resistance of 1- to 2-year-old trees was assessed by measuring the size of resin ducts within bark of the main stem and the mass of resin flowing from simulated feeding damage. Resin flow relative to duct area was much lower in radiata pine than in Corsican pines that are resistant to weevil feeding in the uK, indicating that NZ radiata pine transplants are likely to be highly susceptible. Local population size is influenced by the availability of pine root stumps after clearfelling. The short rotation of radiata pine and a likely shorter weevil generation time could increase weevil abundance and damage relative to the uK. however, larvae are likely to face competition from previously introduced bark beetles, and possibly native fungi, that rapidly exploit the bark of root stumps after felling. In particular, competition with Hylurgus ligniperda, which has an early spring flight and potential for two generations per year, is likely to reduce the number of weevils emerging from root stumps. Overall, pine weevil is likely to have less economic impact in NZ than in northern Europe.

Migration of Bats along a Large River Valley in Southwestern Poland

Abstract Several European bat species migrate long distances of >1,000 km, but information on migration routes is poor or anecdotal, or both. We investigated migration of bats along the Oder River valley in southwestern Poland to determine the significance of large river valleys as migration corridors for bats. We determined direction of bat movements from visual observations and sequence of echolocation signals received by 2 bat detectors, from March to November 2007. The predominant activities of bats were directional flights in spring (March–May) and autumn (mid-August–October) and foraging in summer (June–July). In spring, most bats flew northward, and in autumn, southward. In autumn, the movement occurred over a longer time and there were fewer bats migrating than in spring. We conclude that river valleys are migration flyways for bats that travel long distances and those that travel short distances, and that differences between spring and autumn migration may be related to food supply, to energy dem...

Flight Phenology of MaleCactoblastis cactorum(Lepidoptera: Pyralidae) at Different Latitudes in the Southeastern United States

ABSTRACT Long term trapping studies of the invasive moth Cactoblastis cactorum (Berg) were conducted at various latitudes from Puerto Rico to South Carolina. Three flight periods per year were identified at the 5 temperate sites studied, which covered the majority of the infested range on mainland United States. In general, the 3 flight periods across a latitudinal gradient from south Florida to central, coastal South Carolina were a spring flight during Feb–-May, a summer flight during Jun–Aug, and a fall flight during Sep–Nov. At any 1 site, each flight period lasted about 2 months. In the tropical areas of the Florida Keys and a Caribbean Island, the insect exhibited overlapping generations. Previous studies of this insect (as a biological control agent) report 2 flight periods per year in its native range of Argentina and its introduced range of Australia and South Africa. A synthetic pheromone-baited trap was a good indicator of generational time, and we suggest that trapping assays in these areas wi...

Seasonal dispersal of water beetles (Coleoptera) in an agricultural landscape: a study using Moericke traps in northwest Spain

Information on flight dispersal in water beetles in the Iberian Peninsula is scarce. This study provides new data on the dispersion flight phenology of 21 species captured using Moericke traps in an agricultural system in León province (NW Spain) during two annual cycles (1992 and 1993). The species captured form part of the assemblage of aquatic Coleoptera commonly found in stagnant environments in the centre of the Iberian Peninsula. Most of them are good flyers and colonisers. These flights are related to two environmental variables: mean atmospheric temperature and rainfall. The results show a clear relation between temperature and the flight period as most of the specimens dispersed during peaks of high mean daily temperatures, and a negative relation with rainfall. With regard to phenology, two types of dispersion strategy were identified: flights in the middle of summer to escape from drought and flights in spring and autumn for colonising new habitats. The first group includes Hydroglyphus geminus (Fabricius) and, in particular, Helophorus brevipalpis Bedel, whose great abundance in the dispersal stage is related to parthenogenetic reproduction and the rapid production of a large number of colonising females. The second strategy corresponds to univoltine species with overwintering adults such as Helophorus alternans Gené or species from the genus Hydroporus Clairville.

Quail poisoning in a child

It has been well known since ancient times that the consumption of quail may be deleterious to health. The European quail sub-species (Coturnix coturnix coturnix), common to Europe, North Africa, and western Asia is indeed potentially poisonous to humans, but only during the autumn migration (not during their return flight in spring). Quail poisoning is an acute dietary-toxicological syndrome. In this case report, we describe a rare, non-fatal case of quail poisoning in a 12-year-old boy. The victim was admitted to hospital 5 hours after the consumption of quail because of the signs and symptoms, as well as laboratory findings (elevation of serum muscle enzymes, myoglobinuria) significant of acute rhabdomyolysis. He was treated symptomatically with bed rest, forced continuous diuresis, urine alkalization, and maintenance of fluid and electrolyte balance. The victim recovered completely without sequelae after 8 days hospitalization. The aetiology of this syndrome is still unclear. It has been suggested that a toxic effect or a genetic sensitivity plays a major role. Many cases of quail poisoning in adults have been reported previously on the island of Lesbos during autumn. To our knowledge, this is the first case reported in a child.

Timing of egg hatch by early-season codling moth (Lepidoptera: Tortricidae) predicted by moth catch in pear ester- and codlemone-baited traps

AbstractThe use of the timing of moth catch in traps to predict the start of egg hatch by first-generation codling moth,Cydia pomonella(L.), in apple,Malus domesticaBorkh. (Rosaceae), was evaluated with ethyl (E,Z)-2,4-decadienoate (pear ester) and (E,E)-8,10-dodecadien-1-ol (codlemone) lures. Two sets of paired traps baited with either lure were placed in each of seven orchards and checked daily during the spring flight in 2000 and 2001. Rearing of field-collected eggs and sampling of fruit for injury were used to estimate the date of first egg hatch. Moth catch in traps baited with codlemone and pear ester occurred approximately 144 and 105 degree-days prior to the start of egg hatch, respectively. The effectiveness of using the timing of sustained moth catch in traps baited with these lures as a biological reference point (Biofix) to predict the start of egg hatch when traps were checked every 3–4 d was evaluated in 11 orchards from 2000 to 2002. The calendar date for the start of sustained moth catch in traps baited with either lure varied widely among orchards and years. Significant differences in mean cumulative degree-days from first sustained moth catch until egg hatch were found among male moth catch in codlemone-baited traps and total and female moth catch in pear ester-baited traps. Adjusting the Biofix based on daily temperature thresholds significantly changed the cumulative degree-days required until egg hatch only for female moth catch. No significant differences were found in the accuracy of predicting the date of egg hatch using either the codlemone or pear ester lure or by adjusting the Biofix date using daily temperature thresholds. The cumulative degree-day totals required from Biofix until egg hatch had the lowest variability when the Biofix was (i) based on the sustained catch of female moths in a pear ester-baited trap and (ii) adjusted with a temperature threshold for moth activity.

Climatic trends and advancing spring flight of butterflies in lowland California

AbstractMany studies, largely from cool‐temperate latitudes, have investigated the relationship between the timing of biological events and changes in climatic conditions during the past few decades. Relatively little is known about the response of plants and animals at lower latitudes. Here we show that the average first spring flight of 23 butterfly species in the Central Valley of California has advanced to an earlier date over the past 31 years. Among the species that have appeared significantly earlier, the average shift is 24 days. Climatic conditions (largely winter temperature and precipitation) are found to explain a large part of the variation in changing date of first flight. These results suggest a strong ecological influence of changing climatic conditions on a suite of animals from a mid‐latitude, Mediterranean climate.

Tomicus piniperda (Coleoptera: Scolytidae) initial flight and shoot departure along a north-south gradient.

The exotic pine shoot beetle, Tomicus piniperda (L.) (Coleoptera: Scolytidae), established in the north central and northeastern United States (U.S.) and adjacent regions in Canada, is regulated by a federal quarantine that restricts movement of pine material during specific times of the year based on the beetle's life history. Although climatic variation occurs across T. piniperda's range, a single set of dates is used for timing the movement of pine logs. We monitored T. piniperda spring flight, fall shoot departure, and air and internal tree temperatures at three sites along a 300-km north-south gradient in Michigan and Indiana. We also estimated dates for initial spring flight (12 degrees C threshold) and fall shoot departure (0 degrees C threshold) across an 850-km gradient using historical temperature records (1901 to 1999). Average daily temperatures in fall 1997 (8 October to 12 December) and spring 1998 (20 February to 21 April) were 1.8 to 2.4 degrees C colder, respectively, at the northern field site than at the southern field site. Fall shoot departure began at approximately the same time (day 289 to 290) at all three field sites, but complete shoot departure was extended by 3 wk at the southern site (day 336) compared with the northern site (day 317). T. piniperda adults were first captured in funnel traps on calendar day 86 at the northern site and on day 59 at the central and southern field sites. Peak flight occurred at approximately the same time (day 86) at all three sites. Within-shoot temperatures were very similar to air temperatures in the fall and aboveground inside-bark temperatures were similar to air temperatures in the spring. Average predicted dates based on historical temperature records varied by 31 d for initial shoot departure and 84 d for initial spring flight between northern Michigan and southern Indiana. Because considerable variation can occur in T. piniperda behavior across a broad geographic range, dates specified in the U.S. Federal quarantine should be adjusted according to local temperatures.

Differences in responses to α-pinene and ethanol, and flight periods between the bark beetle predators Thanasimus femoralis and T. formicarius (Col.: Cleridae)

The responses of the bark beetle predators Thanasimus femoralis (Zett.) and Thanasimus formicarius (L.) (Col.: Cleridae) to a combination of α-pinene and ethanol, and Pheroprax ®, the aggregation pheromone of Ips typographus (Col.: Scolytidae), were estimated using baited and unbaited flight barrier traps in central Sweden in 1996 and 1998. In addition, the flight periods of the two Thanasimus species were analysed on the basis of trap catches. Egg development and egg loads of T. formicarius were estimated by dissecting females caught on different dates, and counting the number of medium sized and large eggs in the ovaries. T. femoralis was strongly attracted to Pheroprax ®, but almost no individuals were caught in the traps baited with α-pinene and ethanol. In contrast, T. formicarius was strongly attracted to both kinds of baits. The flight periods of the two Thanasimus species were markedly different. T. formicarius initiated flight in early spring, at about the same time as the first bark beetle species, Tomicus piniperda and Hylurgops palliatus, began to fly. The flight period of T. femoralis started later in the spring, at about the same time as that of I. typographus. Medium sized and large eggs were not present in the ovaries of T. formicarius in the beginning of the flight period. Thereafter, during the major part of the flight period, most females carried medium sized eggs while large eggs occurred mainly in the first half of the flight period.

Butterfly Migrations in Florida: Seasonal Patterns and Long-Term Changes

Flight traps at Gainesville, in north-central Florida, operating from 1984 to spring 2000, separated butterflies migrating into the Florida peninsula (SSE ± 90°) from those migrating out of the Florida peninsula (NNW ± 90°). Five species flew southward in the fall and northward in the spring: Phoebis sennae (L.), Agraulis vanillae (L.), Junonia coenia (Hübner), Urbanus proteus (L.), and Eurema lisa (Boisduval & LeConte). Five species had significant northward flights in spring but no significant migration in fall: Pieris rapae (L.), Vanessa virginiensis (Drury), Vanessa atalanta (L.), Eurytides marcellus (Cramer), and Libytheana bachmanii (Kirtland). Danaus plexippus (L.) had a southward flight in fall but no significant migration in spring. Eurema daira (Godart) switched from a net movement northward in early fall to a net movement southward in late fall, whereas Eurema nicippe (Cramer) maintained a net movement northward throughout the fall. The major migrants differed significantly in the seasonal timing and duration of peak migration. When the numbers trapped were greatest, the proportion of those flying in the migratory direction was greatest. The numbers of spring migrants of A. vanillae increased during the course of the study, whereas both the spring and fall migrations of J. coenia declined. The fall migrations of P. sennae and U. proteus declined sharply. In 1990–1999, the fall migrations of P. sennae and U. proteus averaged only 37 and 15% of what they had averaged in 1984–1989. Reduced planting of soybeans in source areas for migrants probably contributed to these steep declines.

GOES 10 cloud optical property retrievals in the context of vertically varying microphysics

An optimal estimation approach is applied to the physical retrieval of single‐layer cloud optical properties (optical depth and effective radius) using multispectral imager channels on the western Geostationary Operational Environmental Satellite (GOES 10). The retrieval includes diagnostic information pertaining to uncertainty and dependence on a priori assumptions required by the forward model. Satellite retrievals of 0.65‐μm cloud optical depth and effective radius (micrometers) for marine stratocumulus (in both drizzle and drizzle‐free conditions) during the CloudSat Antecedent Validation Experiment and tropical cirrus during the Atmospheric Radiation Measurement (ARM)‐Unmanned Aerospace Vehicle spring flight series are examined together with data from the NASA/Jet Propulsion Laboratory Airborne Cloud Radar (ACR), the ARM Cloud Detection Lidar, and the Colorado State University Scanning Spectral Polarimeter (SSP) instruments. Optical depths are found to be consistent between GOES and SSP after taking into account the degradation of responsivity in GOES channel 1. Colocated ACR/GOES observations support past evidence that passive satellite detection of drizzle size droplets (in terms of a significant positive bias in the retrieved effective radius) may be possible under certain conditions. The ability of a dual lidar/radar active observing system to provide independent information over different cloud particle size regimes is illustrated and speaks to the vertical variability of cloud microphysics. The GOES estimate of effective radius was found to be more representative of the upper 0.5 km of the cirrus clouds examined.

Effect of Soil Moisture on Ovipositional Behavior in the Southern Mole Cricket (Orthoptera: Gryllotalpidae)

The relationship between soil moisture and oviposition in an edaphic insect pest, the southern mole cricket, Scapteriscus borellii Giglio-Tos, was studied in a series of greenhouse experiments. Adults were captured in acoustic calling traps and associated pitfall traps during spring flights in southeastern North Carolina in 1996, 1997, and 1998. Female mole crickets were individually confined in chambers containing 2, 4, 7, 10, and 12% soil moisture. Oviposition and mortality were monitored daily. A significant linear relationship between oviposition and soil moisture was indicated by an increase in the number of crickets ovipositing in response to higher soil moisture levels. Additionally, a delay in oviposition was observed as a response to low soil moisture. There were no significant differences in the number of eggs per ovipositing female, indicating that when oviposition does take place, the individual response of the female is to lay a similar number of eggs regardless of moisture levels. The ovipositional response to a rapid increase in soil moisture was also examined. The rapid increase in moisture resulted in a significantly greater percentage of females ovipositing, as seen in the previous experiments.